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| United States Patent |
6,225,258
|
|
Moore
|
May 1, 2001
|
Controlled release pesticide and fertilizer briquettes
Abstract
An attrition and shatter resistant plant nutrient/pesticide briquette
composition which slowly releases the nutrients and biologically active
materials over long periods of time, comprising slow release plant
nutrient particles, pesticide sorption particles, liquid systemic
pesticide sorbed on the pesticide sorption particles to reduce pesticide
leachability, an adhesive, coating the slow release plant nutrient and
pesticide sorption particles, the composition formed into briquettes by
pressing into dies at elevated pressures and temperatures to make
briquettes resistant to attrition and shattering. A six step method is
provided for the preparation of the slow releasing briquettes from slow
release fertilizers, such as magnesium ammonium phosphate; pesticide
sorption particles, such as activated carbon; liquid systemic pesticides
emulsions, such as imidachloprid fosetyl-Al, and metalaxyl; and adhesives,
such as a vinylidine chloride, 2-ethylhexyl acrylate, acrylic acid resin
emulsion.
| Inventors:
|
Moore; William P. (Hopewell, VA)
|
| Assignee:
|
Lesco Technologies LLC (Strongsville, OH)
|
| Appl. No.:
|
344083 |
| Filed:
|
June 25, 1999 |
| Current U.S. Class: |
504/101; 504/360 |
| Intern'l Class: |
A01N 025/08; C05G 003/02 |
| Field of Search: |
504/360,101
|
References Cited
U.S. Patent Documents
| 2991170 | Jul., 1961 | Szepesi et al. | 71/61.
|
| 3024098 | Mar., 1962 | Austin et al. | 71/29.
|
| 3062637 | Nov., 1962 | Marples et al. | 71/24.
|
| 3190741 | Jun., 1965 | Brandeis et al. | 71/28.
|
| 3647416 | Mar., 1972 | Messman | 71/29.
|
| 3925053 | Dec., 1975 | Kealy | 71/29.
|
| 4539038 | Sep., 1985 | Gombert | 71/64.
|
| 5174804 | Dec., 1992 | Rehberg et al. | 71/3.
|
Other References
Humate International. Information Bulletin. Feb. 1998.*
Humate International. Information Bulletin. Mar. 1999.
|
Primary Examiner: Clardy; S. Mark
Attorney, Agent or Firm: Arter & Hadden LLP
Claims
I claim:
1. An attrition and shatter resistant plant nutrient/pesticide briquette
composition which slowly releases biologically active materials and plant
nutrients to plants in soil, the composition comprises:
(a) slow release plant nutrient particles, exhibiting diameters of between
0.5 and 5.0 millimeters, amounting to between 50 and 95 percent of the
briquette;
(b) pesticide sorption particles, exhibiting diameters of between 0.5 and
5.0 millimeters and an ability to sorb and reduce leachability of liquid
pesticides, amounting to between 2 and 45 percent of the briquette;
(c) liquid pesticide amounting to between 0.1 and 10.0 percent of the
pesticide sorption solids sorbed on the pesticide sorption solids;
(d) an adhesive, amounting to between 2 and 20 percent of the briquette,
exhibiting effective adhesion to the particles of slow release plant
nutrients and the pesticide sorption solids, and a solubility of less than
0.1 gram per 100 grams of water, the adhesive coating the particles of the
plant nutrients and the pesticide sorption solids; and,
(e) the adhesive coated particles being formed into briquettes by pressing
into dies at a pressure and temperature sufficient to make the briquettes
attrition and shatter resistant.
2. The composition of claim 1 wherein the slow release plant nutrient
particles exhibit diameters between 0.8 and 2 millimeters.
3. The composition of claim 1 wherein the slow release plant nutrient
particles amount to between 85 and 95 percent of the briquette.
4. The composition of claim 1 wherein the slow release plant nutrient
particles are selected from the group of slow release plant nutrients
consisting of: magnesium ammonium phosphate, magnesium potassium
phosphate, ureaformaldehyde condensates, sulfur, oxamide, isobutylidiene
diurea, and crotylidine diurea.
5. The composition of claim 1 wherein the pesticide sorption solids
particles exhibit diameters between 0.8 and 2.0 millimeters.
6. The composition of claim 1 wherein the pesticide sorption solids amount
to between 5 and 10 percent of the briquette.
7. The composition of claim 1 wherein the pesticide sorption solids are
selected from the group of sorptive materials consisting of iron humate,
wood flour, ground vegetable seed hulls, starch, silica gel, activated
carbon, paper waste, and clays.
8. The composition of claim 1 wherein the liquid pesticide amounts to
between 0.1 and 5.0 percent of the briquette.
9. The composition of claim 1 wherein the liquid pesticide comprises a
solid pesticide dissolved in a liquid solvent.
10. The composition of claim 1 wherein the liquid pesticide is selected
from the group of biologically active materials consisting of herbicides,
insecticides, fungicides, algaecides, acaricides, nematocides, and
nitrification inhibitors.
11. The composition of claim 1 wherein the liquid pesticide is selected
from the group of systemic pesticides consisting of
1-[(6-chloro-3-pyridinyl)methyl]-N-nitro-2-imidazolidinimine, aluminum
tris (O-ethyl phosphonate),
N-(2,6-dimethylphenyl)-N-(methoxyacetyl)alanine methyl ester, and
1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)-2-butanone.
12. The composition of claim 1 wherein the adhesive amounts to between 2.5
and 5.0 percent of the briquette.
13. The composition of claim 1 wherein the adhesive is selected from the
group of thermoplastic resins consisting of vinylidene chloride,
2-ethylhexyl acrylate, acrylic acid, vinyl acetate, butadiene, natural
rubber and combinations thereof.
14. The composition of claim 1 wherein the adhesive coating the particles
of the plant nutrients and the pesticide sorption solids is a
thermoplastic resin and the coated particles are formed into briquettes by
pressing into dies at a temperature higher than the softening temperature
of the thermoplastic resin, and cooled to a temperature lower than the
softening temperature of the thermoplastic resin.
15. The composition of claim 1 wherein the adhesive coating the particles
of the plant nutrients and the pesticide sorption solids is a
thermoplastic resin, provided as an aqueous dispersion or emulsion
containing between 30 and 70 percent water.
16. The composition of claim 1, additionally containing a die lubricant
amounting to between 0.1 and 0.5 percent, selected from the group
consisting of vegetable oils, mineral oils, lignin sulfonate solutions,
polyethylene glycols, and polyethylene glycol ethers.
17. The composition of claim 1 wherein the coated particles are formed into
briquettes by pressing into briquette shaped dies at pressure between 1500
and 2500 pounds per square inch at temperatures between 80 and 160.degree.
C., and then cooled to a temperature lower than 60.degree. C.
18. A six step method of preparing attrition and shatter resistant plant
nutrient/pesticide briquettes for slow release of plant nutrients and
pesticides to plants in soil, the method comprising:
(a) sizing particles of slow release plant nutrients, amounting to between
50 and 95 percent of the briquettes, so that more than 80 percent of the
particles exhibit diameters between 0.5 and 5.0 millimeters;
(b) sizing particles of pesticide sorption solids amounting to between 2
and 45 percent of the briquettes and exhibiting an ability to sorb and
reduce leachability of liquid pesticides, so that more than 80 percent of
the particles exhibit diameters between 0.5 and 5.0 millimeters;
(c) admixing liquid pesticide, amounting to between 0.1 and 10.0 percent of
the briquette, with the pesticide sorption solids until the liquid
pesticide is sorbed so that the leachability of the liquid pesticide is
substantially reduced;
(d) comingling the sized particles of slow release plant nutrients and
pesticide sorption solids containing the sorbed liquid pesticides;
(e) coating the comingled particles with an adhesive, exhibiting effective
adhesion to particles of slow release plant nutrients and pesticide
sorption particles and a solubility of less than 0.1 gram per 100 grams of
water, amounting to between 2 and 20 percent of the briquette; and,
(f) forming the adhesive coated particles into briquettes by pressing into
briquette shaped dies at a pressure between 1500 and 2500 pounds per
square inch at a temperature between 80 and 160.degree. C.
19. The method of claim 18 wherein the adhesive is a thermoplastic resin
selected from the group consisting of vinylidene chloride, 2-ethylhexyl
acrylate, acrylic acid, vinyl acetate, butadiene, natural rubber, and
combinations thereof.
Description
FIELD OF THE INVENTION
This invention relates to the fields of pesticides and plant nutrients, and
more particularly to pesticides and plant nutrients, combined into
briquettes; the pesticides and plant nutrients exhibiting separately
controllable releases throughout long periods of time. The new pesticide
and plant nutrient composition comprises controlled release plant nutrient
particles, and pesticides sorbed on particulate sorption solids, combined
in the form of attrition and fracture resistant briquettes. The sorptive
solids on which the pesticides are sorbed exhibit the ability to
substantially reduce the leachability of the pesticide. The term pesticide
is used herein to mean any, and all, biologically active chemicals used to
beneficially treat plants, including insecticides, herbicides, algaecides,
fungicides, and acaricides. The term sorb is used herein to mean absorb
and/or adsorb. Typical plant nutrients of this invention are magnesium
ammonium phosphate, magnesium potassium phosphate, ureaformaldehyde
polymer and alkylidene diurea compounds. Typical sorption solids of this
invention comprise: iron humate, silica gel, ground vegetable seed hulls,
starch, wood flour, lignin, activated carbon, and paper waste.
BACKGROUND OF THE INVENTION
The prior art has provided several slow release fertilizers which work by
occluding soluble fertilizer materials within agglomerates bound together
by water insoluble binders. For example nitrogen, phosphorus, potassium
and micronutrients may be bound together with ureaformaldehyde resins, or
as in the case of U.S. Pat. No. 3,925,053 calcium sulfate hemihydrate may
be used as a binder.
U.S. Pat. No. 3,647,416 discloses that bonded fertilizers may be produced
in the form of a briquette using ureaformaldehyde resin as the binder.
U.S. Pat. No. 3,024,098 also discloses a ureaformaldehyde based fertilizer
which is prepared by compressing into agglomerates to provide briquettes
or spikes with high resistances to crushing.
Compressed briquettes have also been prepared with improved nitrogen
release when isobutylidiene diurea was the main source of nitrogen.
There has been less information in the prior art regarding controlled
release of pesticides than of plant nutrients. There has been some success
reported in controlling pesticide release rates when granular pesticides
were coated or encapsulated with water insoluble plastics such as
polyvinylchloride as in U.S. Pat. No. 3,062,637.
In U.S. Pat. No. 5,174,804 a fertilizer/pesticide composition was disclosed
which included a fertilizer and a pesticide admixed with a binder to form
a briquette in which the fertilizer occludes the pesticide, with the
briquette essentially free of water soluble materials. This briquette when
placed in the soil releases nutrients and pesticides into the soil over an
extended period of time.
Although U.S. Pat. No. 5,174,804 advanced the art of controlled release
plant nutrients and pesticides, it did not provide a method for separate
control of the release of the pesticides and the plant nutrients. It also
does not provide for wide variations in the amounts of pesticide or plant
nutrient materials in a briquette product.
OBJECTS OF THE INVENTION
It is an object of this invention to provide an improved plant
nutrient/pesticide briquette composition which releases pesticide and
plant nutrients throughout a long period of time.
It is another object of this invention to provide an improved plant
nutrient/pesticide briquette composition which provides plant nutrients
and pesticides, the releases of which are separately controllable.
It is a further object of this invention to provide an improved plant
nutrient/pesticide briquette composition wherein liquid pesticide is
sorbed on, or in, a particulate filler to control the leaching of the
pesticide from the briquette for longer periods of time.
It is a further object of this invention to provide a plant
nutrient/pesticide briquette which exhibits improved physical integrity,
using pesticide sorbed on pesticide sorption solids, which are coated on
plant food granules by means of a thermoplastic adhesive.
It is a further object of this invention to provide an improved method for
preparing plant nutrient/pesticide briquettes, requiring small amounts of
thermoplastic adhesive.
SUMMARY OF THE INVENTION
To attain the aforementioned objects and to improve existing
fertilizer/pesticide compositions of the prior art, I have discovered a
composition which slowly releases both pesticides (biologically active
materials) and plant nutrients throughout a long period of time. This new
composition is particularly effective because a liquid biologically active
material is sorbed on pesticide sorption particles which have the ability
to sorb pesticides and reduce their leachability. The pesticide sorption
particles and particles of slow release plant nutrients are coated with a
small amount of adhesive, and then compressed to form attrition and
shatter resistant briquettes. Surprisingly, the briquettes release both
the liquid pesticide and the plant nutrients at slow rates, and the
release rates of the biologically active materials may be independently
varied by changes in the amount of, and properties of, the pesticide
sorption particles, and by the amount of pesticide sorbed thereon. The
slow release properties of the plant nutrients and the pesticides may be
changed by variations in the amount of adhesive used in coating the slow
release nutrient granules, and the pesticide sorption particles prior to
briquetting, and by the conditions under which the nutrient granules and
the sorption particles are bound together into attrition and shatter
resistant briquettes. The method of combination, and the amounts of the
ingredients combined are critical to the effectiveness of the new
composition.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed to an attrition and shatter resistant
plant nutrient/pesticide briquette composition which slowly releases
biologically active materials and plant nutrients to plants in soil. A
composition has been discovered which provides these desirable, and
heretofore unavailable, properties. The composition comprises slow release
plant nutrient particles, having diameters between 0.5 and 5.0
millimeters, amounting to between 50 and 95 percent of the briquette. When
the nutrient particles are significantly larger, or smaller, the attrition
and shatter resistance of the briquettes are substantially reduced. The
same effect is observed when the plant nutrients concentrations are
outside of the 50 and 95 percent range.
The effective composition of this invention requires pesticide sorption
solids, exhibiting diameters of between 0.5 and 5.0 millimeters and an
ability to sorb and reduce leachability of liquid pesticides, amounting to
between 2 and 45 percent of the briquette. Some variations in the particle
size of the pesticide sorption solids are tolerable, but significant
amounts outside the foregoing size range does not provide the desired
resistance to attrition and shattering of the briquettes. The pesticide
sorption solids must have an ability to absorb, adsorb, or both, liquid
pesticides so that the leachability of the liquid pesticides is reduced.
This reduction in leachability is usually effected by sorption onto solids
with high surface areas, but may also be achieved by dissolution of the
liquids into materials on the surface of the solids, or by simple
occlusion in the sorption solids. The exact type of sorption may be
varied, but it must significantly reduce the leachability of the liquid
pesticide applied. The amount of sorption solids may be varied over a
substantial range depending upon the type and amount of pesticide
employed.
In the instant invention a liquid pesticide, amounting to between 0.1 and
10.0 percent of the pesticide sorption solids, is sorbed on the pesticide
sorption solids. Solid pesticides in this system are ineffective and allow
unacceptably high leach rates. Amounts of pesticides, less than 0.1
percent provide unacceptably slow release rates from the briquettes and
more than 10 percent pesticide concentration provides higher than
desirable pesticide release rates and poor briquette resistance to
attrition.
The effective composition contains an adhesive, amounting to between 2 and
20 percent of the briquette, which exhibits effective adhesion to both the
particles of slow release plant nutrients and the pesticide sorption
solids and a low solubility of less than 0.1 gram per 100 grams of water.
The adhesive coats the individual particles of the plant nutrients and the
pesticide sorption solids. When less than 2 percent adhesive is used
attrition and shatter resistance is not effective, and when more than 20
percent is used pesticide release is impaired by the presence of excess
adhesive. A water solubility of the adhesive of less than 0.1 gram per 100
grams of water is necessary to prevent rapid degradation of the briquettes
in damp soil with earlier than desired release of the pesticide and plant
nutrient contained therein.
The adhesive coated particles are formed into briquettes by pressing into
dies at pressures and temperatures sufficient to make the briquettes
attrition and shatter resistant. The adhesive may be partially cured
before the coated particles are pressed into dies with the cure completed
in the die as effected by the die pressure and temperature, or the
complete cure of the resin may be effected in the die. The shape, or size,
of the die is a matter of choice depending upon the desired end use of the
briquette. The temperature and pressure used in the die to produce the
attrition and shatter resistant briquettes may be arranged depending
largely upon the type and amount of adhesive employed, and the speed with
which the die is filled, pressed, and discharged.
The composition is particularly effective when the slow release plant
nutrient particles have diameters between 0.8 and 2 millimeters and where
these particles amount to between 85 and 95 percent of the briquette.
A wide variety of slow release plant nutrient particles may be used in the
instant composition and preferred plant nutrients used are magnesium
ammonium phosphate, magnesium potassium phosphate, ureaformaldehyde
condensates, sulfur, oxamide, isobutylidiene diurea, and crotylidine
diurea.
The composition is particularly effective when the pesticide sorption solid
particles have diameters between 0.8 and 2.0 millimeters. For effective
performance of the composition, the amount of pesticide sorption solids
must be controlled within rather narrow limits. Most effective performance
is obtained where the pesticide sorption solids amount to between 5 and 10
percent of the briquette.
The preferred pesticide sorption solids are the materials iron humate, wood
flour, ground vegetable seed hulls, starch, silica gel, activated carbon,
paper waste, and clays.
The amount of liquid pesticide sorbed on the pesticide sorption solids, and
thereby contained in the controlled release pesticide and fertilizer
briquettes must be maintained at a low level to prevent rapid leaching of
the pesticide. Preferred compositions contain liquid pesticide amounting
to 0.1 and 5.0 percent of the briquette.
Liquid pesticides may be used directly for sorbing onto the pesticide
sorption solids. Where pesticides are normally solid at ambient
temperatures, the solid may be dissolved in a liquid solvent and the
liquid derived therefrom may be effectively used as a liquid pesticide for
sorbing on the pesticide sorption solids.
The type of liquid pesticides used in the new controlled release
composition may be selected from any biologically active material which
may be put in liquid form and which may be sorbed onto sorption solids and
thereby have its leachability significantly reduced. Particularly
effective and important biologically active materials for the instant
composition are herbicides, insecticides, fungicides, algaecides,
acaricides, nematocides, and nitrification inhibitors.
The amount of adhesive required for the composition to be effective is the
amount that covers all of the granules in the composition. The adhesive
preferably amounts to between 2.5 and 5.0 percent of the briquettes.
A variety of resins may be used as the adhesive with success but the
preferred adhesive is one of the following thermoplastic resins:
vinylidine chloride, 2-ethylhexyl acrylate, acrylic acid, vinyl acetate,
butadiene, natural rubber, and combinations thereof.
A particularly practical and effective composition is obtained when the
adhesive, coating the individual particles of the plant nutrients and the
pesticide sorption solids, is a thermoplastic resin and the coated
particles are formed into briquettes by pressing into dies at a
temperature higher than the softening temperature of the thermoplastic
resin, and then cooled to a temperature lower than the softening
temperature of the thermoplastic resin.
Thermoplastic resins are available commercially as solid, liquids,
emulsions, or dispersions. Aqueous emulsions and dispersions are
environmentally desirable because they require no organic solvents which
must be eventually recovered or lost into the atmosphere. The instant
composition is effective where the adhesive coating the individual
particles of the plant nutrients and the pesticide sorption solids is a
thermoplastic resin, provided as an aqueous dispersion or emulsion which
contains between 30 and 70 percent water.
As a practical means of efficient briquette machine operation a die
lubricant may be added to the particulate materials to be briquetted. In
addition to decreasing damage and wear on the dies, the lubricants usually
improve the surface smoothness of the briquettes produced. To provide the
desired surface smoothness of briquettes of the present composition, it is
preferred that the composition contain a die lubricant amounting to
between 0.1 and 0.5 percent of vegetable oils, mineral oils, lignin
sulfonate liquids, polyethylene glycols, and polyethylene glycol ethers.
The formation of the instant composition into briquettes may be performed
under a variety of conditions depending somewhat on the type and amounts
of pesticide sorption solids and the pesticides employed. A preferred
composition is obtained where the coated particles are formed into
briquettes by pressing into briquette shaped dies at pressures between
1500 and 2500 pounds per square inch at temperatures between 80 and
160.degree. C., and then cooled to a temperature lower than 60.degree. C.
A six step method is the preferred method of preparing attrition and
shatter resistant plant nutrient/pesticide briquettes for slow release of
plant nutrients and pesticides to plants in soil. The method comprises
sizing particles of slow release plant nutrients, amounting to between 50
and 95 percent of the briquettes, so that more than 80 percent of the
particles exhibit diameters between 0.5 and 5.0 millimeters.
The particles of pesticide sorption solids are sized so that more than 80
percent of the particles exhibit diameters between 0.5 and 5.0 millimeters
and amount to between 2 and 45 percent of the briquettes. The pesticide
sorption solids must exhibit an ability to sorb and reduce the
leachability of liquid pesticides.
The liquid pesticide, amounting to between 0.1 and 10.0 percent of the
briquette is admixed with the pesticide sorption solids until the liquid
pesticide is sorbed and the leachability of the liquid pesticide is
substantially reduced.
Then, the sized particles of slow release plant nutrient and pesticide
sorption solids, containing the sorbed liquid pesticides, are comingled.
The comingled particles of slow release plant nutrients and pesticide
sorption particles are coated with an adhesive exhibiting effective
adhesion to the particles of slow release plant nutrients and pesticide
sorption particles, and a solubility of less than 0.1 gram per 100 grams
water. The coating amounts to between 2 and 20 percent of the briquette.
The adhesive coated particles are formed into briquettes by pressing into
briquette shaped dies at a pressure between 1500 and 2500 pounds per
square inch at a temperature between 80 and 160.degree. C.
The preferred method of preparation is achieved where the adhesive is one
of the following thermoplastic resins: vinylidine chloride, 2-ethylhexyl
acrylate, acrylic acid, vinyl acetate, butadiene, natural rubber, and
combinations thereof.
There are important practical needs for controlled release pesticides and
plant nutrient combinations for fertilizing plants growing in soils, while
at the same time, protecting the plants from damage from insects, mites,
and fungi. Some of the plants which need these treatments are found in
ornamental beds and include roses, azaleas, rhododendrons, poinsettias,
hydrangeas, and forsythias. These plants are perennials, but are moved, or
changed periodically so that it is convenient to fertilize and treat for
pests one, or more times per year. The controlled continuous release of
plant nutrients and pesticides are useful, and it is desirable to have the
pesticides completely released in one year, or less, with about the same
release period for the plant nutrients.
Longer release periods for the pesticides are required where seedlings, or
small trees, are transplanted from nursery beds for growth to attractive
ornamental maturity; or to grow to mature forest trees for harvesting as
pulpwood. For healthy growth, these trees require protection against
pests, particularly fungi, for periods of at least four years. It is
necessary that the pesticides used for the trees need to last for much
longer times than those used for the ornamental bed plants.
It is therefore necessary to have a pesticide delivery system in which the
pesticide release period may be controlled to meet the need of the
particular plants being treated.
1-[(6-chloro-3-pyridinyl)methyl]-N-nitro-2-imidazolidinimine marketed under
the tradename MERIT is an insecticide which is effective against white
grubs and other insects which destroy ornamentals. It is effective when
used as a systemic insecticide. The roots take up the imidachloprid and
translocate it throughout the plant so that when the insects ingest part
of the plant, the insecticide kills them.
Likewise the fungicide aluminium tris(O-ethyl phosphonate, marketed under
the tradename ALIETTE functions as a systemic fungicide. It is used with
nursery grown plants to prevent seedling diseases, particularly pythium
and root rot. N-2,6-dimethylphenyl)-N-methoxyacetyl)alanine methyl ester,
marketed under the tradename of SUBDUE and SUBDUE MAXX, is another
systemic fungicide which treats root rot and pythium.
Another effective systemic fungicide
1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)-2-butanone is
marketed under the tradename BAYLETON (Chemical Abstracts No. 43121-43-3).
It is particularly effective against fusiform rust, and is readily put in
the form of an aqueous dispersion for sorption onto sorptive particles to
substantially reduce its leachability, and increase its long term
effectiveness when combined as part of the instant briquettes.
When the pure pesticide is a solid material it may not be used per se in
the present invention. These pesticides may be effectively used by
dissolving them to form solutions, usually in organic solvents. Also, the
pesticides in either the finely divided solid, or organic solution form,
may be used in the forms of aqueous emulsions or dispersions. The liquid
solutions, emulsions, or dispersions are then effectively sorbed onto
sorption solids to reduce the leachability of the pesticides. The sorption
solids and the controlled release fertilizer granules, may then be
appropriately mixed and formed into briquettes.
EXAMPLES OF THE PREFERRED EMBODIMENT
The examples provided here demonstrate the preparation and the utility of
the present invention and its preferred embodiment.
Example 1
Particulate potassium ammonium magnesium phosphate, analyzing
7-40-6-13(Mg), with 78.6 percent of the nitrogen and 83.3 percent of the
potassium insoluble in cold water, amounting to 900 kilograms was selected
as the slow release plant nutrient and was screened so that 94 percent of
the particles exhibited diameters between 0.6 and 2.5 mm.
Particulate Bentonite clay, amounting to 100 kilograms, selected as the
pesticide sorption solids was screened so that 90 percent of the particles
exhibited diameters between 1.0 and 2.4 mm.
Metalaxyl amounting to 1900 grams was converted to a homogeneous aqueous
liquid emulsion by high shear mixing with 20 kilograms of water containing
1 percent of mineral oil emulsifier, so that the liquid pesticide amounted
to 2% of the total briquette weight.
The metalaxyl emulsion was mixed at ambient temperature with the clay in a
closed Littleford high energy mixer until the emulsion was sorbed
sufficiently to reduce the leachability of the metalaxyl.
The particulate potassium ammonium magnesium phosphate was blended with the
Bentonite based pesticide sorption solids in the Littleford to form a
homogeneous mixture. While the mixture was still in the Littleford mixer,
3 percent by weight of DARATAK 3631, a latex containing polyvinylidene
chloride, 2-ethylhexyl acrylate, and acrylic acid was sprayed evenly on
the homogeneous particle mixture. The coated particles were allowed to
cure at ambient temperature for 18 hours.
A mineral oil die lubricant amounting to 0.25 percent was sprayed onto the
coated particles as they were fed to a Prater Briquetting Machine, which
comprised rollers with opposing half briquette shaped cavities which
produced briquettes weighing 7 grams. The particles were augered into the
space between the rollers and forced into the briquette-shaped dies
(cavities), and there compressed to a pressure of 2500 pounds per square
inch. During the compression temperature in the briquettes was increased
to 190.degree. F. and the briquettes were discharged from the Prater
Machine and cooled to ambient temperature.
The briquettes formed were hard and very resistant to shattering when
dropped 30 feet onto a steel plate. Analyses of the briquettes showed the
following composition:
Components Wt %
Total N 6.01
CWIN 4.75
Total P2O5 34.4
Total K2O 5.3
CWIK 4.4
Total Mg 11.2
Metalaxyl content 1900 parts per million
Example 2
The efficacy of the product of Example 1 was evaluated in the greenhouse
against Pythium fungi in tests where azaleas were grown in small pots.
Prior to treatment, all of the soil used in the tests were innoculated
with a water suspension of Pythium fungi. The tests were carried out by
transferring 10 inch tall azalea plants into 6 inch pots.
A 2-inch layer of soil was placed in the bottom of each pot and a single
fertilizer/pesticide briquette was added. The azalea plant was added and
the pot was packed with additional soil. The test was evaluated after 6
months. In addition to the treatment with the briquettes from Example 1,
pots were treated with: the same material as Example 1, except it
contained no metalaxyl, and with no plant nutrients or pesticides. There
were three pots for each treatment. The results obtained after 6 months
are tabulated as follows:
% of Roots
Treatment Infected Plant Appearance
(1) 6-34-5-11 (Mg) 89.2 plants not hardy, less
No metalaryl than half the growth of (2)
(2) 6-34-5-11 (Mg) 2.1 healthy, good growth
Example/products
(3) Control, no treatment 94.0 poor appearance, little
growth
Example 3
Briquettes were made in the same equipment as Example 1 using the same
technique, but using magnesium potassium phosphate and ureaformaldehyde
condensate powders (36-0-0) combined as the slow release plant nutrients.
Ground soybean hulls were the sorption solids; imidachloprid as a 1%
aqueous emulsion was the liquid pesticide; and butadiene resin latex was
the adhesive to form pesticide/fertilizer briquettes with an analysis as
follows:
Components Wt %
Total N 18.0
CWIN 8.1
Total P2O5 18.0
Total K2O 6.0
CWIK 5.3
Total Mg 6.0
Imidachloprid content 2000 parts per million
Example 4
Briquettes were made in the same equipment as Example 1 using the same
technique, but using ureaformaldehyde condensate powder (36-0-0),
magnesium potassium phosphate, and magnesium ammonium phosphate powders
combined as the slow release plant nutrients. Bentonite clay was the
sorption solids; BAYLETON as a 1% aqueous emulsion was the liquid
pesticide; and DARATAK 3631, a latex containing polyvinylidene chloride,
2-ethyl acrylate and acrylic acid, was the adhesive. The composition of
the briquettes produced was as follows:
Components Wt %
Total N 7.0
CWIN 6.1
Total P2O5 32.8
Total K2O 10.1
CWIK 8.0
Total Mg 11.2
Bayleton concentration 1500 ppm
Example 5
A test was made on Loblolly pine trees in Eastern Virginia sandy soils.
Several treatments were made using the briquettes of Example 4. In the
tests, pine seedlings were transplanted into holes prepared in the sandy
soil. The briquettes were placed in the holes and the seedlings were
placed directly above the briquettes. The tests were run with 12 trees
used per treatment.
The trees were evaluated, and analyzed after growing periods of 1,2 and 4
years. The trees were examined for fusiform rust and the newest leaves
were analyzed for BAYLETON content at each period of evaluation. The
results obtained in the tests are tabulated as follows:
BAYLETON in Last Leaf Percent of Trees
After Showing Fusarium Rust
Treatment 1 Year 2 Years 4 Years after 4 years
Control-no 0 0 0 16
treatment
Example 4 0 0 0 24
Product,
except no
Bayleton
Example 4 1.72 ppm 4.81 0.88 1
Product,
1500 ppm
Bayleton
At the end of four years the trees of the three treatments had produced
positive growth. The trees receiving the fertilizer briquettes with no
BAYLETON were about 5 percent larger than the control trees and the trees
receiving the fertilizer briquettes containing the BAYLETON were about 10
percent larger than the trees receiving the briquettes without the
BAYLETON.
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